Fox won Thursday, as American Idol gave Glee a big boost.Idol earned 15.5 million viewers and a 5.1 in the adults 18-to-49 demographic, down five-tenths from last week. Returning from winter hiatus, Glee nabbed 6.9 million viewers and a 2.7, up 35 percent from its most recent episode last month.Winter TV Preview: Must-see new showsThe penultimate episode of 30 Rock (3.8 million, 1.4) also saw a bump, hitting a season high audience and its biggest since March. 1600 Penn (3.3 million, 1.3) was NBC's only other show that saw a gain.On ABC, series finale of Last Resort (5.4 million, 1.2) was up two-tenths and Grey's Anatomy (8.8 million, 3.0) was steady.8 p.m.CBS: The Big Bang Theory (R) 11.5 million (3.1); Two and a Half Men (R) 8.6 million (2.3)ABC: Last Resort 5.4 million (1.2)Fox: American Idol 15.5 million (5.1) NBC: 30 Rock 3.8 million (1.4); Parks and Recreation 3.9 million (1.7)CW: The Vampire Diaries 2.7 million (1.3) 9 p.m.CBS: Person of Interest (R) 10 million (1.9)ABC: Grey's Anatomy 8.8 million (3.0)Fox: Glee 6.9 million (2.7)NBC: The Office 4.2 million (2.0); 1600 Penn 3.3 million (1.3)10 p.m.CBS: Elementary (R) 7.05 million (1.4)ABC: Scandal 7.7 million (1.5)NBC: Rock Center with Brian Williams 3.7 million (0.8)

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